After I have transferred all data from iPhone 7 to iPhone 11, do I disable old phone?

Follow the directions in this link for the iPhone 7 --> What to do before you sell, give away, or trade in your iPhone, iPad, or iPod touch - Apple Support

After I have transferred all data from iphone 7 to iphone12, do i disable old phone?

after transferred data to new i-phone 12 , i can't edit my setting.

See my post above with the blue words about what to do before you sell or give away your phone. That's what you do.